Depends on your immediate needs, the price, and how much paying a bit more matters.
The 15" Pro is pretty outdated at the moment. Even when it was updated it was using previous generation components that are all that much older now. In all likelihood there will be the first form factor change since 2012 in about a month's time. The new models should use modern silicon, be considerably trimmed down in footprint and weight, while adopting the newest connectivity standards that will keep a computer feeling modern for the next several years. However I would not be surprised if you could buy a used model like you are considering for about half what you'll pay for a new one next month. And the design is tried and true.